South Sudanese government forces were Thursday battling to retake the key rebel-held town of Bentiu, as thousands of civilians continued to flee fighting and peace talks appeared deadlocked.

The fighting has been concentrated in the oil-rich Unity State in the north, and around Bor, capital of eastern Jonglei state, both main rebel strongholds.

Rebel delegates at peace talks held in neighbouring Ethiopia say they will only agree to a truce if the government frees a group of alleged coup plotters detained after the fighting began more than three weeks ago. The government has ruled that out.

Army spokesman Philip Aguer told AFP that troops loyal to President Salva Kiir were now "next to Bentiu", capital of Unity State and one of South Sudan's main oil-producing areas, and that clashes were continuing Thursday.

The UN aid chief in the country, Toby Lanzer, desribed a scene of anarchy inside the town. Shops "have been looted and destroyed", aid agency vehicles were being commandeered by armed gangs and civilians had fled, he said.

A local resident in Bentiu also described an atmosphere of "fear" as civilians braced themselves for an anticipated government onslaught.

Unity State is where much of fledgling oil producer South Sudan's crude is pumped. The country's oil production has dropped by around a fifth since the fighting began, depriving the impoverished nation of a key source of foriegn currency.

The army spokesman said government troops were also locked in combat some 15 kilometres (nine miles) from Bor, situated 200 kilometres (130 miles) north of Juba, the only other major town in rebel hands.

An AFP correspondent in Minkammen, on the other side of the swamps of the crocodile-infested White Nile river from Bor, said hundreds of people are making a perilous journey by boat and on foot to escape the fighting. There were already 80,000 people there -- the single largest concentration of those displaced by the conflict.

Many recounted tales of horror, including civilians mown down with machine guns as they fled, and gunmen torching entire villages and looting crops and livestock.

"They had a machine gun raised up on a sandbank, and they fired and fired and fired as we swam," said Gabriel Bol, a cattle herder. "The bullets were hitting the water, but we knew we could not stop or they'd shoot us."

 

 

The unrest began on December 15 as a clash between army units loyal to President Kiir and those loyal to ex-vice president Riek Machar. It has escalated into war between government troops and a loose alliance of ethnic militia forces and army units who have defected to the rebel side.

The exact toll of the conflict is unclear. The UN has said well over a thousand people have died, although sources from a number of relief organisations say they believe the number of fatalities is well into the thousands.

The US special envoy to Sudan and South Sudan, Donald Booth, shied from calling situation all-out civil war.

"Let's just call it a conflict right now, lets not escalate it ourselves," he told AFP in Addis Ababa, where the East African regional bloc IGAD has been trying to broker a truce.

"There's always a risk of escalation, that's for sure. That's why it's so important that the cessation of hostilities be the key priority," he added, confirming that the fate of political prisoners "has been a stumbling block" for the peace talks.

South Sudan's government is currently holding 11 of Machar's allies, many of them senior figures and former ministers, and has been under pressure from IGAD -- the East African regional bloc brokering the Addis Ababa talks -- as well as Western diplomats to release them as a goodwill gesture.

The demands have been resisted until now, with the government arguing the detainees should be put on trial for their role in what the president says was an attempted coup.

A further source of tension has been rebel allegations that neighbouring Uganda has been providing crucial military support for the government.

"While IGAD countries are pursuing peaceful solution to the conflict, Uganda military are busy killing our innocent population in Jonglei state," rebel spokesman Hussein Mar Nyuot told reporters in the Ethiopian capital.

He said the rebels were "disappointed" by Juba's refusal to free the prisoners, but said talks would continue.

"I can't say actually that the talks are going to collapse," the spokesman said. "We are still hopeful that there is big pressure on (President) Salva Kiir, and that he might actually change his mind."